When I asked one of the Knesset's Foreign Affairs and Defense Committee members last week what he knew about Kela David (David's Sling), he replied honestly that he hadn't a clue. Not wanting to embarrass him further I refrained from asking him about Arrow 3's future performance or about Iron Dome's severe limitations.

He does not know because nobody bothered to tell him, since defense officials make decisions on developing expensive weapons systems without having to explain or persuade policy-makers. In any case, every decision made by the Defense Ministry's Administration for the Development of Weapons and the Technological Industry (known by its Hebrew acronym Maf'at) is eagerly adopted by MKs and ministers alike (that is, if they hear about it).

Thus, following decisions that our elected officials have neither scrutinized nor understood, Israel has assumed second place - after the United States - on the list of countries developing and obtaining anti-missile and rocket systems.

Israel itself is developing and manufacturing no less than four defense systems (Arrow 2, Iron Dome, Kela David and Arrow 3) and has also purchased one system (Patriot) from the United States. Had the ministers and members of the Foreign Affairs and Defense Committee bothered to take an interest, they would have discovered that defense systems are being developed vigorously right under their noses and with their approval. Some of this activity is completely superfluous.

The outstanding cases in point are Kela David and Arrow 3. Although these systems' development began several years ago, it is near impossible to find even one politician who knows their nature or can explain the logic behind their expensive development and purchase.

Two of these anti-missile and rocket defense systems (Arrow 2 and Patriot) were developed and bought a long time before it was decided to develop Kela David. The development of yet another (Iron Dome) was decided on after the Second Lebanon War. An examination of these systems' performance and missions indicates that they are supposed to cover all necessary ranges, from four-kilometer-range rockets to ballistic missiles with a range of more than 3,000 kilometers. So it is not clear why we need another defense system, whose range overlaps with the existing ones.

Moreover, the cost of achieving Kela David's objectives is so high that it puts the justification for its existence into question. The crux behind the decision to develop Kela David is the need to deal with middle-range rockets (40 to 250 kilometers), like those Hezbollah has. The problem is that Hezbollah has thousands of such rockets (which are relatively cheap), while a Kela David missile will cost about $300,000 to $400,000, according to the manufacturer, Rafael Advanced Defense Systems. Independent experts even estimate the cost at some $1 million each. Thus, it is clear that their high cost means the Israel Defense Forces will not be able to buy large quantities of Kela David missiles, certainly not in the amounts needed to counter the thousands of rockets Hezbollah can launch.

In addition, Kela David has another objective - to defend against cruise missiles. But intercepting rockets has nothing to do with intercepting cruise missiles. Adjusting the system to handle both would increase its price considerably, requiring additional advanced and very pricey sensors, to be added to the old intercepting missiles.

Meanwhile, Israel Aerospace Industries is developing Arrow 3, whose objective is surreal: The system is supposed to provide Israel with a hermetic defense, no less. In other words, no ballistic missile launched toward Israel would reach its target. From a technological perspective, this is simply impossible. As advanced and expensive as the technology may be, it cannot be foolproof.

This conclusion necessarily has far-reaching implications for Israel's policy vis-a-vis a future Iranian nuclear threat. Even one or two nuclear missiles striking the Dan Region would be an intolerable price for Israel to pay. The realization that no defense system can intercept all the ballistic missiles launched at the country should force decision-makers to conclude that they must base their policy on deterrence, not defense. This shift occurred in the United States already more than 40 years ago.

Successive American administrations (and Moscow's leaders, too) started to center their policy vis-a-vis nuclear ballistic threats on deterrence, renouncing missile defense systems completely. The danger is that the developers of Arrow 3 may persuade policy-makers that the system would assure Israel's hermetic defense and that no Iranian missile would reach its target. This is a dangerous illusion, which could result in a defense-based policy that would not only be incapable of preventing catastrophe but would also be terribly expensive.

Ministers and MKs had better start paying attention to the goings-on in Maf'at. This body is adding tens of billions of dollars in obligations onto the state budget, based in many cases on false planning and assumptions. This is not just a waste of public funds - it constitutes a threat to national security.

A State Comptroller's report is expected to be released on this matter soon, to help those ministers who want to understand the critical role that Maf'at plays in shaping the future of the defense system - and our own future, too.

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